<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="lib/react.development.js"></script>
    <script src="lib/react-dom.development.js"></script>
</head>
<body>
    <div class="root"></div>
</body>
<script>
    ReactDOM.createRoot(document.querySelector('.root')).render(123);
</script>
</html>